The encounter happened entirely by accident.
Kenjaku had been returning to Uzushio Island after another week of experimentation on the mainland, his Seal of Transfiguration technique now refined to a ninety-three percent success rate. Hana walked three steps behind him as always, her devotion having crystallized into something that no longer required conscious maintenance—she simply existed in his orbit now, a satellite eternally bound to its planet.
They were passing through a mountainous region claimed by no particular clan, a territory so devastated by decades of warfare that even the bandits had abandoned it. The perfect shortcut, Kenjaku had reasoned, with no human obstacles to slow their progress.
He had not accounted for inhuman obstacles.
The cursed energy hit him like a physical blow, a wave of malevolence so dense and concentrated that it momentarily staggered even his ancient consciousness. Beside him, Hana collapsed entirely, her shinobi training useless against spiritual pressure of this magnitude.
Kenjaku steadied himself, his borrowed heart racing with something that might have been fear in a lesser being. He recognized this energy signature. Had studied it extensively in both his lives—as Marcus Chen the fan, and as Kenjaku the ancient sorcerer.
Ryomen Sukuna.
The King of Curses.
The strongest jujutsu sorcerer in history.
Here. Now. In the flesh.
Kenjaku had known, intellectually, that Sukuna existed in this era. The Heian period was Sukuna's golden age, the time when he had terrorized Japan as a living natural disaster. But knowing something intellectually and confronting it directly were very different experiences.
The pressure intensified as its source approached. Through the trees ahead, Kenjaku could see a figure emerging—four arms, two faces, a body that radiated power like heat from a furnace. Sukuna moved with the casual arrogance of a being who had never encountered a genuine threat, his four eyes scanning the landscape with lazy contempt.
Those eyes settled on Kenjaku.
"Oh?" The King of Curses paused, genuine interest flickering across both faces. "A sorcerer. And one who can stand in my presence without dying. How rare."
Kenjaku forced his body to relax, drawing on centuries of experience to project calm he didn't entirely feel. "Ryomen Sukuna. I've heard stories."
"Have you?" Sukuna's smile was a terrible thing, promising violence and suffering in equal measure. "And yet you don't run. Foolish, or powerful? Let's find out."
He moved.
Even with Kenjaku's enhanced perception, Sukuna's speed was difficult to track. One moment he was twenty meters away; the next, his fist was driving toward Kenjaku's face with force sufficient to level mountains.
Kenjaku dodged. Barely.
The air displacement alone sent him tumbling backward, his footing lost despite cursed energy reinforcement. He rolled with the impact, coming up in a defensive stance that he knew was utterly inadequate against his opponent.
"Powerful, then." Sukuna's smile widened. "Good. I was getting bored with weaklings."
The battle that followed was less a fight than a desperate survival exercise.
Kenjaku threw everything he had at the King of Curses. Cursed spirits from his collection, released in waves that Sukuna dismantled with contemptuous ease. Barrier techniques that shattered against casual strikes. Binding vows hastily constructed and immediately broken by sheer spiritual pressure.
Nothing worked.
Sukuna was simply too strong. Too fast. Too overwhelming in every conceivable dimension of combat.
"Cleave," the King announced lazily, and invisible blades carved through Kenjaku's defenses, slicing his borrowed body in a dozen places simultaneously. Only cursed energy reinforcement prevented immediate dismemberment.
"Dismantle." A different attack, targeting the very structure of his being, trying to unravel him at a fundamental level. Kenjaku barely deflected it, the effort costing him more energy than any previous battle in his centuries of existence.
He was going to die here.
The realization crystallized with perfect clarity. For all his planning, all his preparation, all his accumulated power and knowledge, he had stumbled into a confrontation with the single most dangerous being in jujutsu history. And he was losing.
Badly.
But even as despair threatened to overwhelm him, another part of Kenjaku's consciousness was analyzing, calculating, searching for any possible advantage.
Sukuna was stronger. Faster. More experienced in direct combat.
But he was also arrogant. Contemptuous. So certain of his own superiority that he wasn't taking this fight seriously.
And Kenjaku had one ability that Sukuna had never encountered. One technique that the King of Curses had no defense against, because it operated on a level that raw power couldn't address.
Idle Transfiguration.
The technique that touched the soul directly.
It was a desperate gamble. Sukuna's spiritual defenses were presumably as overwhelming as his physical capabilities. The technique might simply fail against a being of such magnitude.
But it was the only option Kenjaku had left.
He let Sukuna's next attack connect.
The blow shattered three ribs and sent him crashing through several trees, his body broken and bleeding. But the impact had served its purpose—it had brought him into direct physical contact with the King of Curses.
And in that moment of contact, Kenjaku activated Idle Transfiguration at maximum intensity, perceiving Sukuna's soul for the first time.
It was magnificent.
Terrifying.
Incomprehensible in its complexity and power.
Sukuna's soul was not like a human's soul. It was something else entirely—a twisted mass of malevolence and hunger and absolute, unconditional pride. It burned like a dark sun, radiating the spiritual pressure that had brought Hana to her knees and nearly overwhelmed Kenjaku himself.
But it was still a soul.
And souls could be sealed.
Kenjaku didn't try to modify Sukuna directly. He wasn't that foolish. Any attempt to reshape the King of Curses' essence would be detected and countered immediately.
Instead, he did something subtler. Something that exploited the momentary contact to inscribe a seal so small, so carefully hidden, that even Sukuna's overwhelming spiritual senses might miss it.
A seed.
A dormant trigger, buried in the depths of Sukuna's soul, designed to activate only under specific conditions.
Conditions that Kenjaku would control.
The contact broke as Sukuna kicked him away, apparently unaware of what had just happened. Kenjaku crashed through more trees, his body screaming in protest, his cursed energy reserves nearly depleted.
"Disappointing," Sukuna declared, advancing on his fallen opponent. "I thought you might provide entertainment, but you're just another insect pretending to be something more."
He raised his hand, preparing a finishing blow.
"Malevolent Shrine."
The words triggered something in Kenjaku's memory—Marcus Chen's memory, specifically. Malevolent Shrine was Sukuna's Domain Expansion, a technique so powerful that it didn't even require a barrier to function. A sure-hit attack that would simultaneously unleash Cleave and Dismantle on everything within its range.
If Sukuna activated it, Kenjaku would die instantly.
But Sukuna never got the chance.
Kenjaku activated his seed.
The seal he'd inscribed on Sukuna's soul bloomed into sudden, overwhelming life. It wasn't an attack—Sukuna could have deflected any attack Kenjaku threw at him. Instead, it was something far more insidious.
A binding.
A spiritual contract, enforced by the seal patterns Kenjaku had learned from the Uzumaki, targeting not Sukuna's power but his access to that power.
The first binding locked away Domain Expansion entirely, severing the connection between Sukuna's consciousness and the ability to manifest his Malevolent Shrine. The technique still existed within him, but he could no longer reach it—like a word on the tip of one's tongue, forever out of grasp.
The second binding targeted Cleave, the precision cutting technique that made Sukuna so deadly at close range. The ability didn't disappear, but the seal disrupted the spiritual pathway that activated it, making the technique impossible to use.
The third binding sealed Dismantle, the broader cutting attack that could unravel complex structures. Same mechanism, same result.
The fourth binding was the most important. It targeted Sukuna's ability to serve as a vessel for reincarnation—the technique that would eventually allow him to possess Yuji Itadori a thousand years in the future. With this pathway sealed, Sukuna could never again take a host body. When he died, he would die permanently.
All of this happened in the space between heartbeats.
Sukuna staggered.
For the first time in his existence, the King of Curses felt something he had never experienced before.
Limitation.
"What—" His voice carried genuine shock, an emotion that might never have crossed his features before. "What did you do?"
He tried to activate Cleave. Nothing happened.
He tried to activate Dismantle. Nothing happened.
He reached for Domain Expansion, for the Malevolent Shrine that should have annihilated his opponent instantly. The technique was there, he could feel it, but something was blocking him. Something had come between his will and his power.
"Impossible," Sukuna breathed. "This is impossible."
Kenjaku forced himself to stand, his broken body held together by will and cursed energy. Blood dripped from a dozen wounds. His vision was blurring, consciousness threatening to fade. But he was alive.
And Sukuna was no longer invincible.
"You're wrong," Kenjaku said, his voice steady despite his injuries. "Nothing is impossible for someone who understands the principles. You're powerful, Sukuna—more powerful than anything I've ever encountered. But power without technique is just force. And force can be redirected, contained, sealed."
Sukuna's face contorted with rage—a new expression for a being who had never had cause for genuine anger. He launched himself at Kenjaku with killing intent that warped the very air.
But without Cleave and Dismantle, he was reduced to purely physical attacks.
Still devastating. Still faster and stronger than anything human. But no longer absolutely overwhelming.
Kenjaku activated Idle Transfiguration on himself, reshaping his body to optimize for speed and endurance. His injuries didn't heal—the technique didn't work that way—but his physical capabilities increased dramatically, giving him just enough edge to evade Sukuna's furious assault.
"You sealed my techniques," Sukuna snarled, pursuing with relentless aggression. "You SEALED them. I'll tear you apart. I'll make your death last for centuries. I'll—"
"You'll do nothing." Kenjaku dodged another strike, his enhanced body moving faster than should have been possible for his level of injury. "Without your domain, without your cutting techniques, you're just a very strong sorcerer. Dangerous, yes. But not invincible. Not anymore."
He released three cursed spirits simultaneously—the strongest remaining in his collection—and used the distraction to create distance between them.
Sukuna destroyed the spirits in seconds, but those seconds gave Kenjaku time to prepare his next move.
The Seal of Transfiguration had worked once. It could work again.
But not on Sukuna directly. The King of Curses was now actively defending his soul, his spiritual awareness focused inward to detect any further intrusion. Kenjaku would never get another clean shot at that level of attack.
However, there were other options.
"Hana!" Kenjaku's voice carried across the battlefield, reaching his subordinate where she lay unconscious from Sukuna's initial spiritual pressure. The command was reinforced with a pulse of cursed energy, a wake-up call that bypassed her traumatized nervous system.
She stirred. Groggily rose. Saw the battle.
"Master—"
"Run. Uzushio Island. Tell Hiroshi what happened here. Tell him—" Kenjaku dodged another of Sukuna's attacks, his margin of survival shrinking with each exchange. "Tell him the King of Curses is real, and he's coming for everyone."
Hana hesitated for only a moment before her conditioning took over. She ran, her shinobi training pushing her body to maximum speed despite the lingering effects of spiritual trauma.
Sukuna noticed her departure but didn't pursue. His attention was fixed entirely on Kenjaku, his rage demanding satisfaction from the being who had dared to limit him.
"You think you can escape?" The King's voice carried something almost like humor beneath the fury. "You've slowed me down, insect. I'll admit that. But I'm still the strongest. Still the king. And kings don't forgive treason."
"I'm not trying to escape," Kenjaku replied. "I'm trying to win."
He activated his maximum technique—Maximum: Uzumaki—channeling every remaining cursed spirit in his collection through the seal-enhanced projection he'd developed during his Uzumaki studies. The blast that erupted from his palm was easily the most powerful attack he'd ever produced, a column of pure cursed energy that would have vaporized most opponents instantly.
Sukuna caught it with one hand.
"Impressive," the King acknowledged, crushing the attack through sheer spiritual pressure. "But not impressive enough."
He advanced again, his four arms reaching for Kenjaku with murderous intent.
And Kenjaku smiled.
"You're right," he said. "Not impressive enough to defeat you directly. But enough to serve its purpose."
The Maximum: Uzumaki hadn't been meant to hurt Sukuna. It had been meant to empty Kenjaku's cursed energy reserves, creating a specific spiritual condition that he'd been preparing for weeks.
A binding vow.
In exchange for sacrificing all his remaining power, Kenjaku gained a single, absolute command that reality itself could not refuse.
"Seal."
The word carried the weight of everything he'd given up, enforced by principles that transcended normal jujutsu. It wasn't an attack. It wasn't a technique. It was a statement—a declaration of intent backed by the universe's own enforcement mechanisms.
Sukuna froze.
Not from damage or disruption, but from the binding vow's absolute authority. For one eternal moment, he was held in place by forces beyond even his comprehension.
And in that moment, Kenjaku inscribed his final seal.
Not on Sukuna's soul directly—the King's defenses were too strong for that now. Instead, Kenjaku targeted the connection between Sukuna and the world itself, the spiritual pathways that allowed him to interact with reality.
The seal was elegant in its brutality. It didn't limit Sukuna's power further; it limited his existence. From this moment forward, the King of Curses would be unable to maintain physical form indefinitely. His body would deteriorate, his consciousness would fragment, and eventually—perhaps years from now, perhaps decades—he would fade entirely.
Unless he found a way to break the seal.
Which, without Domain Expansion or his cutting techniques, would be nearly impossible.
The binding vow released. Sukuna staggered, suddenly aware that something fundamental had changed in his relationship with reality.
"What... what have you done?" His voice carried something unprecedented: uncertainty.
Kenjaku collapsed, his body finally failing from the accumulated damage. He had nothing left—no cursed energy, no physical reserves, barely enough consciousness to observe the results of his work.
But he was smiling. That distinctive smile that never quite reached the eyes, now carrying genuine satisfaction.
"I've ended your reign," he said. "Not today. Not tomorrow. But eventually, inevitably, permanently. The seals I've placed on you cannot be removed by force, Sukuna. They're part of your soul now, as fundamental as your own existence. You'll spend the rest of your limited life searching for a way to break them, and you'll fail. Because the techniques I used to create them don't exist in your understanding of jujutsu."
He laughed, the sound weak but triumphant.
"I've taken the strongest being in history and turned him into a dying animal. How's that for a 'weakling'?"
Sukuna stood frozen, processing what had been done to him. His face—both faces—cycled through emotions that he had never experienced before. Shock. Denial. Rage. Fear.
And finally, something almost like respect.
"You..." The King's voice was quiet, dangerous. "You're not what you appear to be. No sorcerer of this era could have done what you've done. No human could have conceived of techniques like these."
"I'm not human," Kenjaku agreed, his vision fading. "Not anymore. Maybe not ever."
He slipped into unconsciousness, his final coherent thought being a desperate hope that his gamble had worked—that Sukuna would be too weakened, too confused, too focused on understanding his new limitations to simply kill him while he lay helpless.
The darkness took him.
And somewhere in that darkness, a part of him that was still Marcus Chen felt a profound satisfaction.
He had just defeated the King of Curses.
He had fundamentally altered the course of jujutsu history.
He had proven himself worthy of the villain's role he had chosen.
Not bad for a former accountant from the Midwest.
Kenjaku awoke to the smell of herbs and the sound of gentle waves.
His body was wrapped in bandages, his wounds treated with a skill that suggested professional medical attention. The ceiling above him was familiar—wooden beams, traditional construction, the distinctive style of Uzushio Island.
He had survived.
"You're awake." Hiroshi's voice came from somewhere to his left, tired but relieved. "We weren't sure you would recover. Your injuries were... extensive."
Kenjaku turned his head slowly, finding the Uzumaki scholar sitting beside his futon with a cup of tea in his hands. Beyond him, Hana knelt in a position that suggested she hadn't moved in days, her eyes fixed on Kenjaku with desperate intensity.
"How long?" Kenjaku's voice was a rasp, barely audible.
"Nine days. Your assistant reached us four days after leaving you. She told us what happened—or as much as she understood of it." Hiroshi's expression carried something Kenjaku couldn't quite identify. "She said you fought Ryomen Sukuna. And survived."
"More than survived." Kenjaku forced himself to sit up, ignoring the protest of healing muscles. "I sealed him. His Domain Expansion. His cutting techniques. His ability to take hosts. All of it, locked away forever."
Hiroshi stared at him for a long moment, clearly struggling to process this claim. "That's... if what you're saying is true, you've done something that generations of our greatest masters considered impossible. Sukuna was always assumed to be beyond the reach of sealing techniques. His power was simply too great."
"His power is still great," Kenjaku corrected. "But power and technique are different things. I didn't try to contain his strength—that would have been futile. I targeted his access to specific abilities, severing the pathways that connect his will to his techniques."
He paused, considering how much to reveal.
"The methods I used... they're new. Developed from combining your tradition with mine in ways that neither has attempted before. Soul-anchored seals, inscribed through direct spiritual manipulation rather than physical media."
Hiroshi's eyes widened. "The abandoned research. The soul-binding theory that our ancestors gave up on—you actually made it work?"
"I did. And I used it to cripple the most dangerous being in existence." Kenjaku met the scholar's gaze directly. "Your clan's knowledge made this possible, Hiroshi. Without what I learned here, Sukuna would have killed me, then continued his rampage across the land. Instead, he's been reduced to a shadow of his former self—still dangerous, but no longer invincible."
The implications hung in the air between them.
Hiroshi was silent for a long moment, clearly wrestling with the magnitude of what he was hearing. Finally, he spoke.
"This changes everything."
"Yes," Kenjaku agreed. "It does."
The days that followed were a blur of recovery and negotiation.
Kenjaku's battle with Sukuna had done exactly what he'd hoped: it had established his value to the Uzumaki in terms they couldn't ignore. A being who could seal the King of Curses was an ally worth any price, a strategic asset beyond calculation.
The clan's leadership—previously cautious about sharing advanced knowledge with an outsider—suddenly became remarkably cooperative.
Kenjaku was granted full access to the restricted third floor of the library. He was invited to private sessions with the clan's most accomplished sealmasters. He was offered resources, assistance, even permanent residence on the island if he desired it.
He accepted everything they offered while giving away as little as possible in return.
The Seal of Transfiguration remained his secret. He shared the theoretical framework—enough to prove his claims about combining traditions—but kept the specific implementation details to himself. The Uzumaki could study his work for generations without reverse-engineering the technique.
Meanwhile, Kenjaku continued to refine his abilities, using the recovered time to process what he'd learned from the Sukuna encounter.
The seals he'd placed on the King of Curses were holding. He could feel them through the spiritual connection that bound all his soul-work together—four distinct bindings, each maintaining its structure against Sukuna's attempts to break free.
The King was still out there somewhere, still alive, still unimaginably powerful in raw terms. But without Domain Expansion, without Cleave and Dismantle, without the ability to take future hosts, he was no longer the apocalyptic threat he had once represented.
He was merely a monster among monsters.
And monsters could be managed.
"You seem pleased," Hana observed one evening, as Kenjaku studied a particularly complex seal diagram by candlelight.
"I am pleased." He didn't look up from his work. "I came to this world expecting to build power gradually over centuries. Instead, I've already eliminated the single greatest threat to my long-term plans. The timeline has accelerated significantly."
"What happens next?"
Kenjaku set aside the diagram, giving his subordinate his full attention. She had recovered from the trauma of the Sukuna encounter, though the experience had clearly deepened her already-obsessive attachment. She looked at him now like a devotee gazing upon a god.
"Next, I continue building. The Uzumaki sealing knowledge is valuable, but it's only one component of what I need. I want to study the major shinobi clans—their bloodlines, their techniques, their potential for modification. I want to establish networks of influence across the continent. I want to prepare for the changes that will reshape this world in the coming decades."
He smiled, that distinctive expression that had become as natural as breathing.
"The Warring States Period won't last forever. Eventually, someone will find a way to unite the clans—to create the hidden villages that will define the next era of shinobi history. I intend to be positioned to influence that transition. To shape the new order according to my own design."
Hana nodded, accepting his vision without question. "And Sukuna? He'll try to hunt you down."
"Eventually, yes. Once he's processed what happened to him, once he's exhausted other options for breaking the seals, he'll come for me." Kenjaku's smile didn't waver. "I'm counting on it. A great villain needs a nemesis, Hana. Someone whose hatred defines their existence, whose opposition gives meaning to the conflict."
He stood, moving to the window to gaze out at the moonlit sea.
"Sukuna will spend years trying to destroy me. He'll become my shadow, my persistent threat, the darkness that justifies my every action. And in the end, when he finally catches up to me..."
He paused, considering futures that might never come to pass.
"I'll be ready."
Far from Uzushio Island, in a ruined temple deep in the mountains, Ryomen Sukuna sat in absolute stillness.
He had not moved in three days. Had not eaten, not slept, not done anything but probe the seals that now bound his very soul.
They were perfect.
He hated admitting it, but the work was flawless. Every attempt to force the bindings failed. Every technique he could still access proved useless against the spiritual chains. The seals were simply beyond his ability to break—designed by someone who understood soul manipulation at a level Sukuna had never encountered.
The being who called himself Shimoda Kenichi. The ancient thing wearing a young man's body.
Kenjaku.
Sukuna had known many sorcerers over his centuries of existence. Had killed most of them, absorbed some of them, respected perhaps three. But none had ever done what Kenjaku had done.
None had ever made him feel small.
The rage that filled him was unlike anything he had experienced before. It burned cold rather than hot, a patient fury that demanded satisfaction no matter how long it took. Sukuna had time—perhaps not as much as before, given the seal limiting his existence, but enough.
Enough to plan.
Enough to learn.
Enough to find a way to break what had been done to him, and then to visit suffering upon the one responsible that would echo through eternity.
"You think you've won," Sukuna whispered to the empty air, as if Kenjaku could hear him. "You think your clever seals have ended this. But I am the King. I am the strongest. And kings do not stay chained forever."
He rose, his four arms flexing with restrained power.
"Enjoy your victory while you can, little monster. Because when I break free—and I will break free—I will make you understand exactly what it means to challenge Ryomen Sukuna."
His smile matched Kenjaku's in its distinctive wrongness.
"I will make your death into art."
The declaration hung in the silent air, a promise that would shape the next century of both their existences.
The greatest villain of the era had just created his own nemesis.
And the story was only beginning.